That is the primary reason any nation uses nukes. But in order to be a credible defense, the opposing nation has to believe that you have some reasonable first strike capability. If you think about it, the difference between an actual first strike, and responding on the first day of a war is not that different from a logistics standpoint.

Anyone that says nukes will prevent you from being attacked needs to learn history. Every nation with nukes, except N Korea, has been attacked or/and lost a war. What we do not know is what will happen when 2 nuke powers get involved in a war with each other. I have heard that the Pentagon has wargamed India/Pakistan and it always ends up in a nuclear exchange.

The man who damns money has obtained it dishonorably; the man who respects it has earned it

I don't think war is ever necessary it is just a matter of where we individually decide to value personal freedom and choices.

Naturally I'll say "So when Hitler was cutting a swath through France, Greece and Russia, the French, Greeks and Russians should have just let the Wehrmacht through and acquiesced to all Nazi demands and terms? After all, no war is ever necessary." And the logical question about the Japanese in China in the same period. Not to mention the Russians invading Finland.

It takes two, at least, to make a war. You could always just let an invading army through and allow it to take over. You don't have to fight back.

If Trump where half as smart as he thinks he is, he'd be twice as smart as he really is.

Of course it does. Do you expect common sense from countries that spend millions on nuclear weapons when they have so much poverty within their borders?

I would not put it under "common sense." It is just about how once things escalate they are hard to de-escalate. For an example, go to YouTube and re-watch the 1980s film, "Countdown to Looking Glass" which I have heard was taken from wargaming. It is the perfect example.

The man who damns money has obtained it dishonorably; the man who respects it has earned it

Am I the only one who thought it really odd that Japan and South Korea didn't throw a punch when evidence came to light that North Korean agents were kidnapping their citizens, including children?

Perhaps the spectre of a tactical nuclear response is enough to keep all of North Korea's neighbors in line. It's like a crack head walking around the mall waving a gun. All the store owners are willing to give him their merchandise, and let him have his way with their employees in the hopes that he will leave them alone.

France Lost IndochinaLost Suez Canal with Brits, not a major attack I concede

OK, I shouldn't say that the nuclear force prevents attacks. It does prevent an attack that is sufficient to threaten the nation's sovereignty. The motivation for Britain and France to have their own nuclear force has been questioned given that it is assumed that Britain and France would only enter into nuclear war if it was part of a NATO mission. Both nations feel that they need a guarantee that they can exercise purely as a national decision (as unlikely as such a decision would ever be made).

In general the use of nuclear weapons to do anything other than prevent a takeover is met with considerable discussion. I will admit that the USA had a nuclear torpedo. The general feeling is that nuclear material does not spread as well in water as in air, so a very limited nuclear option is much more viable (i.e. including removal of cruise missile submarines like Oscar that threaten sea convoys).https://en.wikipedia.org/wiki/Oscar-class_submarine

Quote: France Nuclear Force Posture and Doctrine

France relies on nuclear deterrence as an ultimate guarantee of French sovereignty. [27] French officials describe the function of nuclear deterrence as "aiming to protect [the country] from any form of state actor aggression against the [country's] vital interests, regardless of its origin or its form." [28] Over the years, this core policy has been reaffirmed by various presidents, (Chirac, Sarkozy, and Hollande) as well as in the 2008 and 2013 White Papers on National Defense and Security. [29] Although the definition of France's vital interests is left vague, analysts agree that it covers the free exercise of sovereignty as well as integrity of national and overseas territories, and extends beyond the protection against nuclear attack. [30] For example, in 2008 President Sarkozy stated "Our nuclear deterrence protects us from any aggression against our vital interests emanating from a state―wherever it may come from and whatever form it may take." [31]

OK, I shouldn't say that the nuclear force prevents attacks. It does prevent an attack that is sufficient to threaten the nation's sovereignty. The motivation for Britain and France to have their own nuclear force has been questioned given that it is assumed that Britain and France would only enter into nuclear war if it was part of a NATO mission. Both nations feel that they need a guarantee that they can exercise purely as a national decision (as unlikely as such a decision would ever be made).

No nation besides the USA has made a nuke on their own without direct assistance or espionage. By this I do not mean AZD and Face read how-to then go to the hardware store and buy a bunch of parts after reading it on the internet. I mean the USA helped the Brits. Probably to have more than one nuke adversary to the Russians, who had the Rosenbergs to teach them. Not sure where France got their help, but they helped the Israelis.

France having their own nukes makes some sense as back in the day Warsaw Pact troops could have made it from the GDR to France in days, it happened before. The Brits then still had a large empire to defend. The USSR probably would gladly have helped India to balance China. China then returns the favor to Pakistan.

Looking at this pattern, N Korea is still a wildcard. Israel is not balanced, but they are stable. What does N Korea do with a nuke? They do not have the population to occupy any neighbors. Maybe they could take S Korea, but they have to know they would never keep it. They have no navy to be able to work an occupation of Japan. China and Russia are so far out of the question to be laughable.

This still leaves what I will call a "Tony Soprano Problem." If you remember the show, Tony did not always want to fight back. He hated his sister but when the Russians slapped her around he had to hit back or "how will it look?" Obviously, a nuke attack means the end of N Korea and everything in it. But how much sabre rattling does a POTUS put up with?

Finally, what does N Korea have? Having a "nuke" and a "nuclear weapon" are two different things. Lets say Face and AZD, the two guys here most inclined to try to build things, do go to Home Depot, AMZN, and a few other places and get what we need. We build the nuke, but the thing is the size of a RV! Useless as a weapon!

A weapon must be delivered. Even a nuke must be delivered with some accuracy. It has to be small enough to sit on a missile since N Korea has no heavy bombers. Can they do that? Maybe. Maybe not.

The man who damns money has obtained it dishonorably; the man who respects it has earned it